Pervious concrete pavements (PCP) have been successfully constructed in low-to-medium volume roads attributed to their sustainability benefits. Several studies have investigated the hydrological performance of PCPs, but limited attention has been given to the structural and environmental aspects. Thus, the objective of this study was to monitor the structural, hydrological and environmental performance of two PCP parking lots built using in-situ and ready-mix methods. Structural distresses were classified based on the distress identification manual, while the infiltration tests were performed every three months for three years to quantify the clogging rate. Joints/edges formed the weakest zones, while inefficient maintenance caused 98% clogging within 18 months. Further, in-situ mixing was 17% cheaper and 0.74% carbon-intensive than ready-mix technology. Overall, this research is envisioned to pave way for the development of guidelines that classify distresses and severity levels specific to PCPs, which also cover adequate maintenance recommendations for field implementation.

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The use of nondestructive ultrasonic pulse velocity (UPV) testing to assess the hardened properties of pervious concrete (PC) mixtures is an emerging research area. Further, UPV has been successfully used to determine the effective flow resistivity (EFR) of asphalt concrete and cement concrete pavements. However, no research studies have focused on understanding PC characteristics using EFR. Thus, the major objectives of this study were to assess the suitability of UPV testing for characterizing PC mixtures and to quantify their EFR, which is a measure of the material’s characteristic impedance and is dependent on the mix variables along with porosity. Thirty-six control and sand-modified PC mixtures were prepared with four aggregate gradations, and three levels each of water-to-cement (w/c) and aggregate-to-cement (a/c) ratios. Test results indicated that EFR was significantly dependent on the mix variables, with aggregate gradation being the most influential factor (six and eight times higher than w/c and a/c ratios, respectively). Lower EFR or higher sound absorption capacity was reported for PC with higher porosities. The sand-modified PC mixtures had higher EFR (by 4%–12%) than the control PC, and consequently lower sound absorption capacity, attributed to the presence of mortar that densified the mixes. Further, good-to-excellent correlations were obtained for various PC properties with UPV and EFR, which underscored the potential of UPV in characterizing PC. The major contribution of this research was the development of a simple, fast, and cost-effective approach, which can be suitably adopted as a quality-control test to determine PC mixture properties.

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The major objective of this study was to evaluate the performance characteristics of control and sand-modified pervious concrete (PC) mixtures through the development of a hybrid multi-criteria decision-making (MCDM) tool to rank the materials and recommend the most optimal performing products. A full-factorial experimentation was adopted to analyse porosity, density, permeability, and compressive strength for 36 PC mixtures. A hybrid MCDM tool involving analytical hierarchy process, Entropy, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), and VlseKriterijumskaOptimizacija I Kompromisno Resenje (VIKOR) methods was used to optimize the multi-response problem into a single output. Based on the results, the water-to-cement ratio may be restricted to a maximum of 0.30 and 0.33 for aggregates varying from 9.5 to 6.7 mm and 6.7 to 4.75 mm, respectively. Likewise, the cement-to-aggregate ratio may be restricted to a maximum of 1:3.75 and1:4.25 for aggregate size in the range 9.5–6.7 mm and 6.7–4.75 mm, respectively. Further, the ranks for various PC mixtures obtained from TOPSIS and VIKOR were identical/ similar for about 80% of the mixtures. The proposed MCDM tools are envisioned to help the decision-makers in selecting the most optimum PC mix based on performance and site-specific requirements, a priori pavement design and construction.@en

Conversion of pervious natural ground into impermeable pavement systems has caused severe environmental impacts such as urban heat islands, increased infrastructure-related greenhouse gas (GHG) emissions and energy consumption, and runoff generation / flashfloods during rainfall events. These phenomena can be addressed with the use of pervious concrete pavement (PCP) systems, which have gained acceptance as sustainable alternatives to conventional materials. However, implementation of PCP technology is limited to low-volume roads, sidewalks, and parking lots attributed to low strength and the need for high quality control during construction compared to traditional pavements along with limited understanding on the end-of-life significance due to the green PCP product. Therefore, the major objective of this research was to develop a pavement system with superior structural and hydrological performance characteristics over traditional PCP, while also quantifying the energy consumed, amount of GHG produced, and costs associated with its design and construction. Thus, a Pervious All-Road All-weather Multilayered pavement (PARAMpave) was conceptualized and designed that comprised a 300 mm square paver block created with a 60 mm lower structural layer overlaid with a 30 mm water-draining surface wearing course pervious concrete layer. The major properties of PARAMpave products included porosity ranging from 17% to 24%, permeability varying from 0.77 cm/s to 1.33 cm/s, and flexural strength between 4.83 MPa and 6.13 MPa, indicating their improved structural and hydrological performance compared to traditional designs. Further, a cradle-to-gate lifecycle approach was utilized to perform a comparative evaluation between PARAMpave and Portland cement concrete (PCC) paver blocks. The PARAMpave products consumed lower energy (8.22% to 8.51%) and emitted lower GHGs (8.23% to 8.43%) compared to PCC blocks of similar dimensions. Additionally, PARAMpave blocks were about 10% cheaper and almost 10% lighter than a PCC paver block. The reduction in GHG emissions, energy consumption, and capital costs indicate that PARAMpave blocks are a sustainable class of roadway products. Also, the strength and permeability magnitudes of PARAMpave indicate that they have high potential for applications in different road classes and diversified weather conditions.@en

The objective of this review paper was to discuss in detail the various sustainability benefits offered by pervious concrete (PC), while also documenting the current state-of-the-art pertaining to mechanical and hydrological characteristics. The prevailing mix design procedures as well as the impacts of additives and recycled materials on behavior of PC have been discussed. Impact of pore morphology on permeability was examined, and a note was made on current rehabilitation techniques for restoring the infiltration rate of clogged PC surface courses. Field studies that focused on design, construction, and performance monitoring of pervious concrete pavements (PCP), were highlighted. Additionally, the contribution of PCP to reduce the environmental impacts of built infrastructure was summarized. The multiple benefits offered by PCP such as runoff mitigation, heat alleviation, energy conservation, and emissions reduction make it a promising material for construction of environment-friendly PC roadways. However, there still exists a vast scope to enhance the material’s characteristics for development of sustainable pavement systems in the urban built environment.@en

Embedded infiltration rings have been historically used to estimate the infiltration properties of pervious concrete (PC) pavements. However, no methodical study has evaluated the effect of the size of embedded rings on the infiltration characteristics of these special pavement systems. The objective of this research was to assess the infiltration rate of PC using a multi-scale, in situ approach through embedding rings of various sizes in pavement slabs. Essentially, this investigation attempted to identify the most appropriate size of the embedded ring that can estimate infiltration rates of PC slabs in a reliable manner. To meet the proposed objective, a multi-scale in situ experimental program was designed, in which five infiltration rings of inner diameter ranging from 100 to 580 mm were embedded into three PC slabs of dimensions 3 × 2.5 × 0.15 m. A surface infiltration test was also conducted on PC slabs and was found to vary from 0.36 to 1.87 cm/s. The embedded infiltration rate (EIR) was estimated using a falling head permeability test by ponding water above the pavement surface and measuring the time taken to drain. EIRs decreased from 1.36 to 0.27 cm/s with increasing ring diameter from 100 to 580 mm. Field tests also indicated that infiltration rates for smaller ring diameters (180 mm and lower) had higher uncertainty, which was attributed to the inability of achieving optimum compaction efforts inside of smaller rings. Based on the findings, the optimum size for estimating the infiltration rate of PC was found to be 270 mm. It is noteworthy that this diameter is in the range suggested by ASTM C1701, Standard Test Method for Infiltration Rate of In Place Pervious Concrete, i.e., 300 mm. This research helped identify the practicable specimen size that could be utilized by researchers and practitioners to estimate the most reliable field infiltration rates through PC.@en

Pervious concrete pavement (PCP) systems allow enhanced infiltration of stormwater through them due to the presence of interconnected porous channels within their structure; thereby preventing urban flooding and augmenting groundwater recharge. The functional performance of PCP is usually evaluated using the surface infiltration (SI) test, in which water that is poured into the infiltration ring (300 mm diameter) is allowed to flow both vertically downward as well as horizontally within the pervious concrete (PC) due to the lack of lateral constraint. Thus, the SI test is not fully capable of simulating the actual water flow in the PCP system during rainfall events. Further, a systematic investigation of the environmental impacts of PCPs has not yet been attempted. Thus, the research objectives of the current study were two-fold: assessment of infiltration parameter in PCP systems using a multi-scale methodology, and computation of embodied energy and greenhouse (GHG) emissions from PCPs using cradle-to-gate approach. To accomplish the research objective, two PC parking lots of dimensions 125 m × 4 m × 0.15 m (A), and 50 m × 6 m × 0.15 m (B) constructed using a single PC-mix type laid on granular sub-base (GSB) of 0.25 m and 0.2 m thicknesses were considered. Over parking lot B, field experiments were performed with infiltration rings of various diameters (ranging from about 100 to 630 mm) embedded into the PC slabs with a provision for draining the water. The results from the multi-scale tests established that the minimum size of infiltration ring required to accurately estimate the infiltration rate of the PC slab was of diameter 300 mm. The full-scale and SI tests on parking lot A confirmed that the infiltration rates through PCP, PC, and GSB varied from 0.05-0.29 cm/s, 0.11-0.32 cm/s, and 0.07-0.11 cm/s, respectively. Further, the strength of parking lot A constructed using in-situ mixing procedure showed 60% higher strength than parking lot B, which was constructed using ready-mixed pervious concrete. Additionally, the embodied energy and GHG emissions in PC were about 3% lower than Portland Cement Concrete (PCC). The preliminary findings indicated that PC not only reduces surface runoff, but also conserves natural resources (fine aggregates). PC also has potential to reduce the amount of emissions into the atmosphere than PCC, which needs further investigation. @en

Pervious concrete (PC) has gained acceptance as a sustainable pavement material because of its ability to capture and infiltrate stormwater through the pavement system, and subsequently augment groundwater recharge. However, a systematic methodology that estimates and assesses the in situ infiltration characteristics of pervious concrete pavement (PCP) systems has yet to be developed. The objective of this study was to establish a rational methodical approach that evaluates the infiltration rates through PC and granular subbase (GSB) layers in a PCP system by utilizing experimental and analytical techniques. Over 20 field test slabs, each measuring4×4×0.15m, were con-structed along a 120-m long stretch using one single PC mix type overlaid on a 0.25-m GSB layer. An experimental field test was designed to estimate the in situ infiltration rate through the PCP system, and was found to vary between 0.11 and 0.32 cm/s. Further, an infiltration test was performed on PC slabs to measure the surface infiltration rate (SIR), which ranged from 0.10 to 1.28 cm/s. Using the principle of conservation of mass, which assumes that the flow rate through each layer in a PCP system is identical, the infiltration rate of the GSB layer was found to be0.07–0.11cm=s. A significant contribution of this study was the development of a generic approach toward characterizing the major in situ infiltration parameters of multilayered PCP systems that incorporate a base and subbase layer, which have the potential to serve as effective hydraulic conduits through the system.@en

The increased urbanization has caused conversion of natural pervious ground into impervious layer due to concretization with respect to pavement construction. The impervious layers have reduced the groundwater recharge and increased the frequency of flash floods and urban heat island (UHI) effects. One of the engineered ways to reduce the effect of impervious layers without affecting the development is to utilize pervious concrete pavements suitably. Pervious concrete pavements provide multiple benefits such as increased groundwater recharge, reduced UHI effects, and skid resistant riding surface. However, the utilization and implementation of pervious concrete pavements in India is very minimal owing to lack of expertise and experience. With an aim to introduce the pervious concrete pavements to larger arena, this paper provides information about two successful case studies regarding construction of pervious concrete pavements as demonstration test sections. The case studies provide information about construction of pervious concrete pavements using new gradations, mix designs as well as functional and structural performance characteristics. The methods used in this study were labor-based, which could easily be implemented by small-scale contractors in locations such as parking lots, pedestrian walkways, fuel filling stations, and highway shoulders.@en

With growing urbanization and associated development of infrastructure, urban heat islands (UHI) have emerged as major challenges, which need to be taken care of, in order to endure sustainable urban conglomerates. In this study, pervious concrete pavements (PCP) systems were designed and constructed to assess if they can serve as best UHI management practices through actual field implementation and testing. A systematic field experimental program was devised, wherein temperature profiles were measured across the depth of PCPs, under both dry and wet conditions. Thermocouples were embedded in PCP and Portland cement concrete pavements (PCCP) to record and compare the temperature profiles. The pavement surface temperature was recorded at 15-minute intervals under dry conditions, while the pavement temperature was examined after every three hours for wet conditions. Wet conditions were simulated by pouring water over the pavements and the temperatures across the pavement thickness were measured. The quantity of water required to decrease the pavement temperature by 1 °C across the depth of the pavements was quantified. Under dry conditions, it was found that PCP system was warmer compared to PCCP, irrespective of the time in one day. The volume of water required was about 38 ml to reduce the surface temperature of PCP by 1 °C. Further, in order to achieve similar reduction in temperature throughout the thickness of the pavement system, the volume of water required ranged from 2620 to 6350 ml. Owing to its impervious nature, no change in temperature was observed in PCCP system even with inundation of water, except at the surface that exhibited very minute reduction. The experimental findings showed that negative impacts of UHI can be countered by using PCP systems as a potential for harnessing evaporative cooling effects that is remarkably higher than conventional pavements.@en